B
Post-quantum TLS readiness
sdn.cz
Secure today, exposed to harvest-now-decrypt-later
Short answer
No. As of 2026-11-03, sdn.cz does not negotiate post-quantum key exchange; it uses x25519 over TLSv1.3 (Quantum Aether grade B), so recorded traffic is exposed to harvest-now-decrypt-later.
| Grade | B |
|---|---|
| Key exchange | x25519 |
| Post-quantum | no (classical) |
| TLS | TLSv1.3 |
| Hosting network | Seznam.cz, a.s. |
| Tranco rank | #5956 |
| Country | 🇨🇿 Czechia: #23/26 (37.5%) |
From our weekly tracker of the top 10,000 sites, scanned on 2026-11-03 · /adoption
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